Direct measurements of the stabilization of single-stranded DNA under tension by single-stranded binding proteins
Abstract
The unzipping and rezipping of a double-stranded DNA molecule is carried out in the presence of two single-stranded binding proteins T4 gp32 and E. Coli SSB protein to determine the effect of the proteins on the stability of single- and double-stranded DNA. The proteins do not have a significant effect on unzipping, indicating that the two proteins do not destabilize the double-stranded DNA; however, both proteins inhibit rezipping. At protein concentrations where the rezipping force response is saturated, E. Coli SSB protein reduces the rezipping force to 5.5±1.5pN , while T4 gp32 completely blocks rezipping on the time scale of the experiment.
- Publication:
-
Physical Review E
- Pub Date:
- August 2007
- DOI:
- 10.1103/PhysRevE.76.021916
- Bibcode:
- 2007PhRvE..76b1916H
- Keywords:
-
- 87.14.Gg;
- 82.37.Rs;
- 87.14.Ee;
- DNA RNA;
- Single molecule manipulation of proteins and other biological molecules;
- Proteins